The whales of the world

baleines Whales are warm-blooded aquatic mammals. They have lungs and must surface to breathe air. They belong to the order cetacea.
They are either mysticetes (baleen whales) or odontocetes (toothed whales, such as dolphins and porpoises). Mysticetes have no teeth. They use baleen plates (fibrous triangular plates) to filter tiny planktonic crustaceans (especially krill, a shrimp-like crustacean) and other types of aquatic organisms. Mysticetes include species such as the humpback whale, the right whale, the gray whale, and the rorqual.

Odontocetes consume more fish and molluscs. Odontocetes include whales such as the sperm whale and the northern bottlenosed whale.

Whales inhabit all the world’s oceans. Where they live is determined by two main factors: surface water temperature and the quantity of food available. Whales feed in upwelling zones (areas where nutrient-rich deep ocean waters rise to the surface) and in areas where ocean currents meet, where they can find high concentrations of plankton.

The incredible migration of whales

Whales migrate seasonally every year. They can cover thousands of kilometres, although they usually remain in the same hemisphere. Between the summer and the winter northern hemisphere whales travel south but without ever meeting southern hemisphere whales. They spend the winter in warm waters where they mate and give birth. In the summer, they head back towards the poles, whose waters are rich in krill and plankton (the main food source of many whales).

Both northern and southern hemisphere whales rarely migrate beyond the equator and there is a six month lag between their migrations. This means that, in winter when whales from the northern hemisphere migrate to their southern mating grounds, it is summer in the southern hemisphere, and whales from the south have already migrated south to their feeding grounds off Antarctica.

Scientists have observed that mysticetes or baleen whales, which have a more diversified diet, migrate a shorter distance than those which feed only on krill.

We know less about odontocete migration, except for sperm whales. Sperm whales form 3 groups: a "nursery" group composed of mothers and calves, sometimes accompanied by other adults, a group of young single males, and smaller groups of the larger males which do not necessarily migrate beyond their hunting areas every year and which seem to spend less time in mating grounds than other sperm whales.

There is only one known case of a whale species altering its migration route. At the beginning of the 19^th century, humpback whales were unknown in the waters around Hawaii. Yet today, the northern Pacific is the best place to see and study them.

The overfishing of large cetacea

In 1946, in a context of an overfishing of large cetacea, the Washington Convention created the International Whaling Commission (IWC) in order to manage commercial whaling. Progressively, the role of the IWC evolved towards whale conservation in its own right although this change has been controversial. Today, the IWC is an international organisation with a membership of 80 countries (including 21 EU member states), which have varying positions on whale hunting.

France is a member of the IWC and has adopted a protective stance towards whales whereas Japan, Norway and Iceland lead a group of countries supporting whale hunting.

Each year the IWC debates a range of issues and, in particular, authorises hunting and sets quotas. Since the 1986 moratorium, whale hunting has been regulated as follows:

Commercial whaling is banned. Norway, Iceland and Russia have opposed this ban and both Norway (600 animals/year) and Iceland (40 in 2007) continue to hunt whales for commercial purposes.
Subsistence whaling: this totals 871 over a 5 year period. This type of whaling relates to native peoples who have a traditional dependence on whales. This includes the USA (natives of Alaska), Russia (natives of Siberia), Denmark (natives of Greenland) and St. Vincent and the Grenadines.
Scientific whaling: Japan practices scientific whaling on a large scale (more than 10,000 whales caught since 1986) and by Iceland (150 animals).

Supporters and opponents of commercial whaling

	In favour of commercial whaling	Against hunting and in favour of protecting whales
Who	Norway Iceland Japan Russia since 1986	21 EU member states 21 EU member states France The majority of Member States
Arguments	Detrimental effect of whales on fisheries (commercially viable ones): many developing countries support this. Integrated management of whale hunting ; hunting is regulated, managed for sustainability Commercial whaling is only to provide a source of food for humans. As only a few countries hunt whales, the impact on stocks will be small. Hunting whales for scientific purposes provides information for biologists that could not be obtained otherwise.	Many whales (baleen, in the southern hemisphere) do not eat fish, they eat krill. All the organisms (products) whales feed on have no commercial value. Removing predators such as whales disrupts the food chain and by the same token the natural environment. The collapse of overfished whale populations has not led to a increase in fish stocks. The precautionary principle should be applied as we have incomplete data on (whale) populations. Whale watching allows sustainable management with higher profits than hunting. This form of tourism is increasing 12% every year and generates a turnover of 1 billion dollars/year whereas whale hunting....

Whale-watching tourism

Whale watching is an increasingly popular activity with tourists all around the world. According to a report by the International Fund for Animal Welfare (IFAW), over 13 million people took part in whale-watching excursions in 119 countries in 2008.

And with 2.1 billion dollar turnover in 2008, the industry is expanding..

This form of tourism offers a sustainable alternative capable of generating profits without hunting whales.

The role of whale cadavers on the deep ocean floor

Since the end of the 1980s new scientific discoveries have shown that the cadavers of whales and other marine mammals supply life on the ocean floor with resources and habitat. The "whale ecosystem" has similar chemical, biological and trophic qualities to deep-ocean hydrothermal vents and cold seeps.

This is the finding of a publication entitled "De l'utilité des baleines" by the association "Robin des Bois", which draws on leading-edge research.

Sources

The references in the section "At Nausicaa, the incredible migration of whales" as well as the following:

ARTICLES

Le Point.fr. "L'Observation des baleines, une filière touristique en expansion". Article du 24/06/09
L. CARAMEL. La Commission baleinière internationale toujours dans l'impasse. Le Monde of June 27th, 09

BOOKS

R. HARRISON et M.M. BRYDEN. Baleines, dauphins et marsouins. Ed. Bordas, 1989
D. ROBINEAU. Cétacés de France. Ed. Fédération Française des Sociétés de Sciences Naturelles, 2005
J.P. SYLVESTRE. Baleines et cachalots. Ed. Delachaux & Niestlé, 1989
L. DOW. La petite Encyclopédie des baleines. Ed. Bordas, 1991
La Baleine. Encyclopédie Larousse des Animaux, 1993. Coll. Vie Sauvage : mers et montagnes